The results of this study indicate that several issues within the public mental health system need to be addressed. First, screening for substance abuse should be conducted for all hospital admissions, with particular attention paid to adult forensic and child and adolescent patients. Second, training protocols for the identification, assessment, treatment, and management of the mentally ill substance abuser should be developed for mental health service providers. Third, treatment programs (both hospital and community based) for patients with the dual disorders of mental illness and substance abuse need to be developed and implemented. These steps would promote appropriate and more effective interventions for this difficult population.